Ti-25Al-14Nb-2Mo-1Fe合金的热变形行为及本构方程的建立  

Hot deformation behavior and establishment of constitutive equation of Ti-25Al-14Nb-2Mo-1Fe alloy

作　　者：程军[1,2] 毛勇[2] 于振涛[1] 牛金龙[1] 余森[1] 张文[1,3] 

机构地区：[1]西北有色金属研究院,陕西西安710016 [2]云南大学材料科学与工程系,云南昆明650091 [3]西北工业大学材料学院,陕西西安710072

出　　处：《金属热处理》2015年第1期146-151,共6页Heat Treatment of Metals

基　　金：云南省应用基础研究面上项目(2008CD075);西安市未央区科技计划项目(201414;201312)

摘　　要：通过热模拟压缩试验研究了Ti-25Al-14Nb-2Mo-1Fe合金在变形温度950~1100℃,变形速率0.001~1 s-1,最大变形程度50%条件下的热变形行为。结果表明,Ti-25Al-14Nb-2Mo-1Fe合金的流变应力对热变形工艺参数(变形温度和变形速率)的敏感性较高,其真应力-真应变曲线具有峰值应力、应变软化和稳态流动特征。采用Arrhenius双曲正弦函数和多元回归处理法确定了合金在试验条件下的应力指数n、变形激活能Q等材料参数,建立了Ti-25Al-14Nb-2Mo-1Fe合金高温变形本构关系模型。The hot deformation behavior of Ti-25Al-14Nb-2Mo-1Fe alloy was investigated at deformation temperatures 950-1100 ℃ with strain rate 0.001-1 s-1 , and the height reduction of 50%by using isothermal simulative compression testing.The results show that the flow stress of the alloy is sensitive to the hot working parameters, such as deformation temperature and strain rate.The true stress-true strain curves exhibit a peak flow stress, flow softening and steady state flow behavior.The stress exponent ( n) and the apparent activation energy ( Q) for hot deformation is calculated based on a hyperbolic-sine Arrhenius-type equation and multiple regression method.Constitutive equation is established for high temperature deformation of the alloy.

关 键 词：TI2ALNB基合金 热变形 线性回归 本构方程 

分 类 号：TG146.23[一般工业技术—材料科学与工程]